Hyperosmotic soft contact lens well-tolerated in treating corneal edema

SAN DIEGO — A novel soft contact lens improved vision and reduced corneal thickness in patients with corneal edema and corneal dystrophy, according to a study presented here.

Perspective from Eric D. Donnenfeld, MD

Claes G. Feinbaum, MD, PhD, discussed the Hyper-CL hyperosmotic lens (EyeYon Medical) at the World Cornea Congress.

Claes G. Feinbaum

“We all know that for the cornea to function properly, it needs to be clear,” Feinbaum said, adding that extent of hydration is a determining factor for clarity. “The aims of any edema therapy are to keep the cornea dry and to fight infections.”

Changes in endothelial cell size and density disturb light entering the eye and excess fluid reaching the stroma scatter light, Feinbaum said.

The Hyper-CL lens creates an osmotic gradient that pulls fluid from the cornea so that the fluid can evaporate from the ocular surface, he said.

“It is a unique design that acts as a pump. No preparation is required. It’s disposable and can include refractive correction by prescription only,” Feinbaum said.

Indications for using the lens include bullous keratopathy, corneal erosion, corneal dystrophy and postoperative corneal edema after cataract and corneal surgery.

Contraindications are similar to those for normal contact lens wear.

The study included 24 patients with a mean age of 61 to 75 years who underwent cataract surgery.

Patients with a baseline corneal thickness of 590 μm were included.

No adverse effects of wearing the lens were reported, although discomfort was noted in three eyes and these lenses were exchanged for a larger diameter lens.

Corneal thickness decreased by an average of 115 μm and visual acuity improved by an average of 1.5 lines, Feinbaum said.

“Safety and efficacy have been established. A larger multicenter study is ongoing in Europe to make sure the method is effective for corneal edema and corneal dystrophies,” he said.– by Matt Hasson

Disclosure: Feinbaum is a consultant for EyeYon Medical and earns royalties from FeinPat Ophthalmics.

Perspective

Eric D. Donnenfeld, MD

The Hyper-CL hyperosmotic lens is an innovative concept for use in patients with corneal edema. A standard and well-accepted therapy for corneal swelling is hyperosmotic sodium chloride drops and/or ointment to clear edematous corneas. In this trial, there was a significant decrease in corneal pachymetry and an increase in visual acuity with the use of the lens in patients who had cloudy corneas following cataract surgery.

A limitation of this trial is that there was no control group, and the natural history of corneal edema following cataract surgery is spontaneous resolution over a few days. A more important trial would be in patients with bullous keratopathy who are awaiting corneal transplantation to determine whether the lens would clear these corneas that are stable at the time of treatment.

Another concern is that contact lenses can cause mild endothelial hypoxia that should be addressed as well. In summary, this is very interesting information, a promising idea, and we will await further study.

Eric D. Donnenfeld, MD

OSN Cornea/External Disease Board Member

Disclosures: Donnenfeld reports no relevant financial disclosures.